1. Field of the Invention
This invention relates to container closures and more particularly to a tamper evidencing container closure.
2. Prior Art
Recently, a heightened emphasis has been placed upon utilization of tamper proof or tamper evident closures for containers, particularly containers utilized for human ingestible materials.
A known class of such containers employs caps or closures having dispensing orifices therethrough. Such orifices may be used in connection with, for example, squeeze bottles or the like, and frequently include a two section cap, a first section including a base top surface having the orifice therethrough and a second section forming a stopper for the orifice. In such caps, the stopper portion is movable from an orifice closing to an orifice opening position. The stopper carrying member may either be an integral part of the closure, as shown, for example, in U.S. Pat. No. 4,124,151, or may be formed as a separate but attached piece as shown, for example, in my co-pending allowed patent application entitled "Dispensing Type-Cap Closure" Ser. No. 326,416, filed Dec. 1, 1981, now U.S. Pat. No. 4,441,637 the teachings of which are herein incorporated by reference.
Such stopper members must, of necessity, be relatively easy to open to allow the container to be used for its intended purpose. However, ease of opening of the stopper allows for possible tampering with the contents to occur. While it has been known to utilize foil or paper seal overlays covering the stopper member, which overlays must be broken or removed prior to openings, such overlays are not a sufficient detriment to tampering, as in the case of stick on overlays which might be surreptitiously opened by steaming or the like, or are an undesired added expense.
It has also been known to make the stopper member physically a part of the cap and to provide a tear strip portion in the connection of the cap to the stopper member (see U.S. Pat. Nos. 3,255,928; 3,651,992; and 4,081,108). While such tear strip portions provide an indication of tampering, they require that the stopper member be molded as a part of the cap, an expensive procedure.
It would therefore be an advance in the art to provide an attached stopper dispensing orifice type closure having means preventing opening of the stopper which means are easily removable but which, when removed, provide an indication of tampering and which means further are both inexpensive and difficult to circumvent.
It would be a further advance in the art if such a tamper evident closure could be provided in connection with a easily attached substantially non-removable cap-container interface.